Fahrenheit 451

I think you are referring to:

"The autumn leaves blew over the moonlit pavement in such a way as to make the girl who was moving there seem fixed to a sliding walk, letting the motion of the wind and the leaves carry her forward."

This quote links the beauty of the autumn elements with the beauty of Clarisse. They are both real in a world full of manufactured illusions. Both Clarisse and the autumn leaves are tangible and organic. Their very presence defies the artificial vacuous world of the State.